Despite all of Guggenheim's acclaim, he pursued his work with a quiet, intense, almost private single-mindedness. He developed an unadorned style in his films that seemed to be a reflection of his own personality. In his more recent films, such as the Academy Award nominated D-DAY REMEBERED, Guggenheim began to explore history from the singular point of view of the individuals who experienced it. The struggle and humanity of a few individuals thrown into harrowing circumstances beyond their control was a story that interested Guggenheim the most. This was a theme that would lead him towards his most personal film of all and his last.

BERGA: SOLDIERS OF ANOTHER WAR, will be the first film, in fifty years of directing and producing, which Guggenheim included himself in the telling of the story. The American soldiers who were sent over to fight in the Battle of the Bulge were sent from his 106th Infinatry Division. And he could have shared their fate if he were not injured in basic training. In his narration he remembers quietly, "They went overseas, and I didn't. And some of them didn't come back. And I've been thinking about it for fifty years, wondering why it didn't happen to me. And that's why I had to tell this story."

Guggenheim's cancer subjected him to a prolonged and debilitating suffering. His struggle to complete the film after he had been diagnosed with cancer was monumental and he exhibited the same dignity as the men he had revered.

No matter what the subject of Guggenheim's films, be it an important monument, historical event or social issue, at the heart of every story lies the heroic struggle of everyman–and Guggenheim's belief that there is dignity in that struggle.

Guggenheim was a guest lecturer at Harvard's Loeb Fellowship in Advanced Environmental Studies, as well as a fellow at both Harvard and Yale Universities. He was a member of the faculty at Harvard's Salzburg (Austria) Seminar in American Studies and received Honorary Doctorate Degrees from Washington University in St. Louis and from American University in Washington, DC.

Guggenheim served as President of the Foundation for the National Archives and was a trustee of the Danforth Foundation and the White House Historical Association. He was a member of Writers Guild of America and the Academy Motion Picture Association of America.